Dispensing drugs through body holes, namely vaginal, anal and nasal delivery, is a widespread and common practice in the art.
Regarding to delivery by anal or vaginal route, this implies operational procedures which impart an overall feeling of discomfort to its users, whereby it represents opportunities for improvement that provide a positive impact among its potential users.
In particular, women represent more than half of world's population and they may suffer from diseases specific to their gender that despite not normally being life-threatening can result in a sharp decrease in quality of life. Several companies are developing new therapies in order to solve these problems and improve the quality of life of women.
The vaginal route has been traditionally used for local delivery of drugs, but is now much more relevant as a plausible route for systemic delivery. The delivery of drugs by vaginal route is usually useful for the prevention and treatment of sexually transmitted diseases and for contraceptives, but new developments in the field of bio-adhesives and liposomes indicate that this might be a useful route to other therapies.
The advantages of delivering drugs through vaginal route are the ease of delivery, the possibility of self-delivery, low systemic exposure to the drug and good permeability to some drugs when compared with other routes of delivery. The low enzyme activity and the possibility for absorbed drug being transferred into the uterus may also benefit the delivery of the drug.
For intra-vaginal delivery of drugs is necessary to use suitable devices. The design of devices for vaginal route delivery should take into account the anatomical and physiological aspects of the vagina. Traditionally, pharmaceutical forms comprise liquids (solutions, emulsions or suspensions), vaginal suppositories or ovula, as well as tablets, capsules or even creams and gels.
Such devices for vaginal route delivery, also commonly named applicators, should allow the correct and properly located application of the drug to be used in the vagina. Delivery through vaginal route requires that applicators are inserted into the vagina, adequately deposit the drug, and then being removed. Since they can produce changes in the mucosa, it is essential that devices assure a level of security that should be evaluated as integral part of vaginal products.
Applicators can be divided into two major groups: disposable (single use) and reusable ones. Generally, single-use applicators are already filled with the drug and properly packaged into blisters while the reusable ones are filled with drug by the user prior to use.
Various designs of such devices are already known in the art, particularly plunger devices or toothpaste shaped tubes, wherein not all of which allow for easy and comfortable insertion, due to the presence of sharp edges.
The design of such applicators should have as main assumptions:                safety, for example in relation to chemical and physical stability of the drug, or seeking prevention of localized trauma associated with its use, and in particular to its insertion;        efficiency, evaluated, e.g., by adequate and consistent localized delivery of the required drug dosage;        acceptance, taking into account the comfort, ease of use and aesthetic aspects.        
Prior art applicators are very rigid and their insertion end may damage the vaginal mucosa. Also, the uneven end of usual applicators collides painfully with vaginal walls while pushing them away against the intra-abdominal forces.
Usual applicators have no insertion depth control, being easily inserted excessively, causing pain and potentially damaging the ostium, which will become especially dangerous during pregnancy.
Finally, in applicators of the prior art, the plunger of the applicator, when the latter is filled and ready for insertion, is located away from the anatomical extent of the user's hand. This cause the user to adopt anatomically incorrect body positions in order to operate the device, as well as requiring the use of both hands. Moreover, the use of applicators of the prior art requires that the patient must rest in a lying position with legs bent, not allowing, for example, its use in the sitting position.
The following is a brief description of devices for delivery of drugs through vaginal route disclosed in prior art documents closer to the present invention.
Patent Application U.S. 2003233077 A1 entitled “Applicator Device for Suppositories and the Like” discloses an applicator for dispensing pharmaceutical products, having a fusiform shape and comprising a body and a plunger for release of ovula.
European Patent EP 1518574 B1, entitled “Cannula for Dispensing Fluid Products for Vaginal and Anal Applications” discloses a cannula for dispensing fluids, for vaginal application, comprising a tubular body and a plunger allowing a controlled release of the drug.
Patent Application U.S. 2003158511 A1 entitled “Vaginal Suppository Delivery Device” discloses a device for dispensing suppositories through vaginal route including a forceps shaped body having upper and lower attachment members cooperating together to confine a passage, a sleeve member and a plunger.
Patent Application U.S. Pat. No. 4,312,347 A, entitled “Positive Pressure Drug Releasing Device” discloses a device for extended delivery of drug for intra-vaginal or intra-uterine drug release. The device has a body including a plunger driven by a compression spring which generates a pressure for expelling the drug in liquid form out of the body defining chamber. At one end of the body there is a membrane restricting the drug delivery flow rate, to provide the patient with the prescribed dosage.
There are further patent documents on the same technical field, such as for example, EP 0910427 B1, EP 1319420 A1, although they do not disclose the technical features of the present invention. Further, they are not as useful as the present solution and they do not provide similar easiness of use as the solution disclosed herein.
In view of the above, there is a need for a delivery device (or applicator) and pharmaceutical forms dispensing mechanism thereof providing for:                manufacture simplicity, for example, due to a dispensing mechanism made of a single part;        simplicity of operation and ergonomics for easy handling and use with only one hand, while providing a comfortable operation;        safety, ensuring the body integrity, namely the vaginal mucosa, and an adequate depth of insertion;        efficiency, ensuring an accurate delivery at the desired location, and        versatility, allowing for a broad use of different pharmaceutical forms to be dispensed, such as, for example, tablets, ovula, capsules, pills, gels, suspensions, and suppositories.        